TWI855693B - Communication device, control method of communication device, and communication control program - Google Patents

Abstract

The communication device (102) or the communication device (103) communicates with a target device using a wireless frame that complies with the IEEE802.11 series of standards. The MAC (Media Access Control) frame of the wireless frame contains frequency channel representation information as relevant information of communication between the device that sends the wireless frame and the target device through a plurality of links that comply with the IEEE802.11 series of standards established in a plurality of different frequency channels that can perform wireless communication that complies with the IEEE802.11 series of standards.

Description

Communication device, control method of communication device, and communication control program

The present invention relates to the transmission and reception of communication-related information in wireless communications.

The WLAN communication standards established by IEEE (Institute of Electrical and Electronics Engineers) are known as the IEEE802.11 series. In addition, the so-called WLAN is the abbreviation of Wireless Local Area Network. The IEEE802.11 series standards include IEEE802.11a/b/g/n/ac/ax specifications.

Patent document 1 discloses that wireless communication caused by OFDMA (Orthogonal Frequency Division Multiple Access) is implemented in the IEEE802.11ax specification. In the IEEE802.11ax specification, high peak throughput is achieved by implementing wireless communication caused by OFDMA.

In order to further improve throughput or frequency utilization efficiency, the IEEE is currently discussing the development of the IEEE802.11be specification as a new specification in the IEEE802.11 series. The IEEE802.11be specification is discussing a technology that allows one AP (Access Point) to establish multiple links with one STA (Station) through multiple different frequency channels to communicate. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2018-50133

[The problem that the invention wants to solve]

Thus, in the IEEE802.11be specification, Multi-Link communication, in which AP and STA establish multiple links with different frequency channels and communicate in parallel, is being discussed. In order to conduct Multi-Link communication, information related to Multi-Link communication, such as the capability information of AP Multi-Link communication, must be communicated between AP and STA. Previously, the MAC (Media Access Control) frame required to properly communicate information related to Multi-Link communication did not exist.

In view of the above-mentioned topic, the purpose of the present invention is to communicate with the target device through the communication information of multiple links established in multiple different frequency channels in accordance with the IEEE802.11 series specifications, using appropriate MAC frames. [Means for solving the topic]

In order to achieve the above-mentioned purpose, the communication device of the present invention is characterized by having: a communication means for communicating a wireless frame conforming to the IEEE802.11 series of standards with other communication devices; a MAC (Media Access Control) frame of the preceding wireless frame communicated by the preceding communication means contains frequency channel indication information as information related to the communication between the device that sent the preceding wireless frame and the target device through a plurality of links conforming to the IEEE802.11 series of standards established in a plurality of different frequency channels that can perform wireless communication conforming to the IEEE802.11 series of standards. [Effect of the invention]

According to the present invention, the communication with the target device can be carried out using appropriate MAC frames through the communication related information of multiple links established in multiple different frequency channels that comply with the IEEE802.11 series standards.

The following is a detailed description of the embodiments of the present invention with reference to the attached drawings. In addition, the configuration shown in the following embodiments is only an example, and the present invention is not limited to the configuration shown in the drawings.

FIG1 shows the structure of the network in which the communication device 102 described in the present embodiment participates. The communication device 102 is an access point (AP) responsible for constructing the network 101. In addition, the network 101 is a wireless network. In the present embodiment, when the communication device 102 constructs a plurality of networks, it is assumed that the BSSIDs of the networks are all the same. In addition, BSSID is the abbreviation of Basic Service Set Identifier, which is an identification element required to identify the network. Furthermore, it is assumed that the SSIDs shown by the communication device 102 in each network are all the same. In addition, SSID is the abbreviation of Service Set Identifier, which is an identification element required to identify the access point. In this embodiment, even when the communication device 102 establishes multiple connections, one SSID is still used.

Furthermore, the communication device 103 is a station (STA) responsible for participating in the network 101. Each communication device supports the IEEE802.11be (EHT) specification and can perform wireless communication that complies with the IEEE802.11be specification through the network 101. In addition, IEEE is the abbreviation of the Institute of Electrical and Electronics Engineers. In addition, EHT is the abbreviation of Extremely High Throughput. In addition, EHT can also be interpreted as the abbreviation of Extreme High Throughput. Each communication device can communicate in the frequency bands of 2.4 GHz band, 5 GHz band, and 6 GHz band. The frequency band used by each communication device is not limited to this, and different frequency bands such as the 60 GHz band can also be used. Furthermore, each communication device can use 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz bandwidths for communication.

The communication devices 102 and 103 can realize multi-user (MU) communication by multiplexing the signals of multiple users by executing OFDMA communication that complies with the IEEE802.11be specification. OFDMA communication is the abbreviation of Orthogonal Frequency Division Multiple Access. In OFDMA communication, a portion of the divided frequency band (RU, Resource Unit) is allocated to each STA in a way that does not overlap with each other, and the carriers allocated to each STA are orthogonal. Therefore, the AP can communicate with multiple STAs in parallel.

Furthermore, the communication devices 102 and 103 establish a link through a plurality of frequency channels and perform multi-link communication. Here, the frequency channel is a frequency channel defined in the IEEE802.11 series of specifications, and refers to a frequency channel that can perform wireless communication that complies with the IEEE802.11 series of specifications. In the IEEE802.11 series of specifications, a plurality of frequency channels are defined in each of the 2.4 GHz band, the 5 GHz band, and the 6 GHz band. In addition, in the IEEE802.11 series of specifications, the bandwidth of each frequency channel is defined as 20 MHz. In addition, by bundling adjacent frequency channels, a bandwidth of 40 MHz or more can be utilized in one frequency channel. For example, the communication device 102 establishes a first link 104 through a first frequency channel of a 2.4 GHz band and a second link 105 through a second frequency channel of a 5 GHz band with the communication device 103, and communicates through the links of the two. In this case, the communication device 102 maintains the second link 105 through the second frequency channel in parallel with the first link 104 through the first frequency channel. In this way, the communication device 102 can improve the throughput of the communication with the communication device 103 by establishing a link through multiple frequency channels with the communication device 103. In addition, the communication devices 102 and 103 can also establish multiple links with different frequency bands in Multi-Link communication. For example, the communication devices 102 and 103 can also establish a third link in the 6GHz band in addition to the first link 104 in the 2.4GHz band and the second link 105 in the 5GHz band. Alternatively, a link can be established through multiple different frequency channels included in the same frequency band. For example, a first link 104 through 1ch in the 2.4GHz band and a second link 105 through 5ch in the 2.4GHz band can be established. In addition, links with the same frequency band and links with different frequency bands can also exist in a mixed manner. For example, the communication devices 102 and 103 may establish a third link through 36 ch in the 5 GHz band in addition to the first link 104 through 1 ch in the 2.4 GHz band and the second link 105 through 5 ch in the 2.4 GHz band. By establishing multiple connections with the communication device 103 in different frequency bands, the communication device 102 can communicate with the communication device 103 using another frequency band even when one frequency band is congested, thereby preventing a decrease in the throughput of the communication with the communication device 103.

In Multi-Link communication, the multiple links established by the communication devices 102 and 103 only need to have different frequency channels. In addition, in Multi-Link communication, the frequency channel interval of the multiple links established by the communication devices 102 and 103 only needs to be greater than 20 MHz. In addition, in this embodiment, although it is assumed that the communication devices 102 and 103 establish a first link 104 and a second link 105, more than three links may also be established.

The communication devices 102 and 103 can perform three modes of communication as Multi-Link communication. One is Asynchronous Mode (Async Mode). In this mode, the communication through each Link in the Multi-Link communication is asynchronous. Specifically, the communication through the first Link and the communication through the second Link are performed at independent timings. Therefore, both the first Link and the second Link can communicate at a timing that is independent of the timing of the other Link. In this case, if the channel intervals between the frequency channels (channels) used in each Link are narrow, the communication of one Link will affect the communication of the other Link. Specifically, if the frequency channels of the links are too close, the communication conducted in one link will be detected by carrier sensing in the other link, so during the period of communication using one link, the communication on the other link will become impossible. Therefore, in Async Mode, the channel spacing between links becomes wider. Another mode is Synchronous Mode (Sync Mode), in which the communication through multiple links is performed synchronously. Specifically, the communication between the first link and the second link starts at the same timing. In this case, since the communication through each link is started at the same time, the communication on one link will not be carrier sensed in the other link, so it does not matter if the channel spacing between the channels used in each link is narrow. Another mode is Semi-Asynchronous Mode (Semi-Async Mode). In this mode, if data communication is in progress through one link and the frequency channel of the other link is idle, the communication through both links will be synchronized. For example, if the backoff counter of the first link becomes 0 and the frequency channel of the second link is idle, the communication through the first link and the second link will start at the same time. In this case, it does not matter even if the backoff counter of the second link is not 0. In addition, when the fallback counter of the first link becomes 0, if the frequency channel of the second link is not idle, only the communication through the first link will be started, and the communication through the second link will not be started. In this mode, when the communication through multiple links is carried out in parallel, since the communication through each link is started at the same time, it does not matter if the interval between the channels used in each link is narrow. The communication devices 102 and 103 can also select the mode to be used in Multi-Link communication based on the channel interval of the multiple links that have been established.

In the case of Multi-Link communication, at least one of the communication devices 102 and 103 is a device that can simultaneously perform data transmission through a certain link and data reception through other links. Alternatively, at least one of the communication devices 102 and 103 can only perform data transmission through other links while receiving data through a certain link. Alternatively, at least one of the communication devices 102 and 103 can only perform data reception through other links while transmitting data through a certain link. Alternatively, at least one of the communication devices 102 and 103 can maintain multiple links at the same time, but when communicating data through a certain link, it cannot simultaneously communicate data through other links. In addition, it is assumed that such a communication device does not support Sync Mode or Semi-Async Mode.

In the case of Multi-Link communication, the communication devices 102 and 103 divide one data and send it to the target device through multiple links. Alternatively, the communication devices 102 and 103 send the same data through each of the multiple links, and use the communication through one link as a backup for the communication through the other link. Specifically, it is assumed that the communication device 102 sends the same data to the communication device 103 through the first link through the first frequency channel and the second link through the second frequency channel. In this case, for example, even if an error occurs in the communication through the first link, the communication device 103 can still receive the data sent from the communication device 102 because the same data is sent through the second link. Alternatively, the communication devices 102 and 103 can also use links differently according to the type of frames or data to be communicated. The communication device 102 can also be, for example, a management frame that is sent through the first link and a data frame containing data that is sent through the second link. In addition, the so-called management frame specifically refers to a Beacon frame, or a Probe Request frame/Response frame, or an Association Request frame/Response frame. In addition, in addition to these frames, a Disassociation frame, an Authentication frame, or a De-Authentication frame, and an Action frame are also referred to as management frames. The Beacon frame is a frame used to report network information. Also, the Probe Request frame is a frame used to request network information, and the Probe Response frame is a frame used to provide network information in response. The Association Request frame is a frame used to request a connection, and the Association Response frame is a frame used to indicate permission for connection or an error, etc. The Disassociation frame is a frame used to disconnect a connection. The Authentication frame is a frame used to authenticate the target device, and the De-Authentication frame is a frame used to disconnect the authentication of the target device and disconnect the connection. The Action frame is a frame required to perform additional functions other than those mentioned above. The communication devices 102 and 103 transmit and receive signals using management frames that comply with the IEEE802.11 series of standards. Alternatively, the communication device 102 may also be such that, when transmitting data related to a photographic image, the interpretation information such as the date or the parameters when the image was taken (aperture value or shutter speed), and the position information are transmitted via the first link, and the pixel information is transmitted via the second link.

Furthermore, the communication devices 102 and 103 can also perform MIMO (Multiple-Input And Multiple-Output) communication. In this case, the communication devices 102 and 103 have multiple antennas, and one of them sends different signals from each antenna using the same frequency channel. On the receiving side, multiple antennas are used to simultaneously receive all signals arriving from multiple streams, and the signals of each stream are separated and decoded. In this way, by performing MIMO communication, the communication devices 102 and 103 can communicate more data in the same time compared to the case where MIMO communication is not performed. Furthermore, when the communication devices 102 and 103 are performing Multi-Link communication, they can also perform MIMO communication in a part of the links.

In addition, although the communication devices 102 and 103 are assumed to support the IEEE802.11be specification, they may also support at least any one of the specifications before the IEEE802.11be specification, that is, the old specifications. The so-called old specifications are the IEEE802.11a/b/g/n/ac/ax specifications. In addition, in this embodiment, at least any one of the IEEE802.11a/b/g/n/ac/ax/be specifications is referred to as the IEEE802.11 series specifications. In addition to the IEEE802.11 series specifications, other communication specifications such as Bluetooth (registered trademark), NFC, UWB, Zigbee, MBOA, etc. may also be supported. In addition, UWB is the abbreviation for Ultra Wide Band, and MBOA is the abbreviation for Multi Band OFDM Alliance. In addition, OFDM is the abbreviation of Orthogonal Frequency Division Multiplexing. Also, NFC is the abbreviation of Near Field Communication. UWB includes wireless USB, wireless 1394, Winet, etc. In addition, it can also support the communication standards of wired communication such as wired LAN.

As specific examples of the communication device 102, a wireless LAN router or a PC may be cited, but it is not limited to these. The communication device 102 may be any communication device as long as it can perform Multi-Link communication with other communication devices. Furthermore, the communication device 102 may also be an information processing device such as a wireless chip that can perform wireless communication that complies with the IEEE802.11be standard. Furthermore, as specific examples of the communication device 103, a camera, a tablet, a smart phone, a PC, a mobile phone, a video camera may be cited, but it is not limited to these. The communication device 103 may be any communication device as long as it can perform Multi-Link communication with other communication devices. Furthermore, the communication device 103 may also be an information processing device such as a wireless chip that can perform wireless communication in accordance with the IEEE802.11be standard. Furthermore, although the network in FIG. 1 is a network composed of one AP and one STA, the number of APs and STAs is not limited thereto. In addition, the information processing device such as a wireless chip has an antenna required to transmit the generated signal.

2 shows the hardware structure of the communication device 102 in this embodiment. The communication device 102 includes a memory unit 201, a control unit 202, a functional unit 203, an input unit 204, an output unit 205, a communication unit 206, and an antenna 207.

The memory unit 201 is composed of one or more memories such as ROM or RAM, and stores various information such as computer programs required for various actions described below or communication parameters required for wireless communication. ROM is the abbreviation of Read Only Memory, and RAM is the abbreviation of Random Access Memory. In addition, as the memory unit 201, in addition to memories such as ROM and RAM, storage media such as floppy disks, hard disks, optical disks, optical magnetic disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, DVDs, etc. can also be used. In addition, the memory unit 201 can also have a plurality of memories.

The control unit 202 is composed of one or more processors such as a CPU or an MPU, and controls the entire communication device 102 by executing a computer program stored in the memory unit 201. In addition, the control unit 202 can also control the entire communication device 102 by the cooperative operation of the computer program stored in the memory unit 201 and the OS (Operating System). In addition, the control unit 202 generates data or signals (radio frames) to be sent in communication with other communication devices. In addition, CPU is the abbreviation of Central Processing Unit, and MPU is the abbreviation of Micro Processing Unit. In addition, the control unit 202 can also have multiple processors such as multi-cores, and control the entire communication device 102 by multiple processors.

Furthermore, the control unit 202 controls the functional unit 203 to execute predetermined processing such as wireless communication, photographing, printing, and projection. The functional unit 203 is hardware required for the communication device 102 to execute predetermined processing.

The input unit 204 receives various operations from the user. The output unit 205 provides various outputs to the user through the monitor screen or the speaker. Here, the output provided by the output unit 205 may be: display on the monitor screen, or sound output or vibration output caused by the speaker. In addition, the input unit 204 and the output unit 205 may be implemented as one module like a touch panel. Furthermore, the input unit 204 and the output unit 205 may be integrated with the communication device 102 or may be independent.

The communication unit 206 controls wireless communication in accordance with the IEEE802.11be standard. In addition to the IEEE802.11be standard, the communication unit 206 can also control wireless communication in accordance with other IEEE802.11 series standards or wired communication such as wired LAN. The communication unit 206 controls the antenna 207 to transmit and receive signals required for wireless communication generated by the control unit 202. In addition, if the communication device 102 supports NFC standards or Bluetooth standards in addition to the IEEE802.11be standard, it can also control wireless communication in accordance with these communication standards. Furthermore, when the communication device 102 is capable of performing wireless communication in accordance with a plurality of communication standards, it may also be configured to have a communication unit and an antenna that support each communication standard. The communication device 102 communicates image data, document data, image data, etc. with the communication device 103 through the communication unit 206. In addition, the antenna 207 may be configured independently of the communication unit 206, or may be configured to be integrated with the communication unit 206 into a module.

The antenna 207 is an antenna capable of communicating in the 2.4 GHz band, the 5 GHz band, and the 6 GHz band. In the present embodiment, although it is assumed that the communication device 102 has one antenna, it may also have a different antenna for each frequency band. Furthermore, if the communication device 102 has a plurality of antennas, it may also have a communication unit 206 corresponding to each antenna.

In addition, the communication device 103 has the same hardware configuration as the communication device 102.

FIG3 shows the functional structure of the communication device 102 in this embodiment. The communication device 102 is composed of a Multi-Link communication capability information generating unit 301, a Multi-Link communication utilization information determining unit 302, and a connection processing unit 304. In addition to these, the communication device 102 is also composed of a MAC (Media Access Control) frame generating unit 305 and a data transmission and reception unit 306.

The capability information generating unit 301 is a block for generating capability information about the Multi-Link communication of the communication device 102. The communication device 102 generates capability information required to notify other communication devices of its capability about Multi-Link communication. The capability information about Multi-Link communication is described in FIG. 5 to be described later. In addition, regarding capability information, the capability information of the device can be notified to other communication devices, or the capability information of the target device can be received from other communication devices.

The usage information determination unit 302 is a block that determines the usage information of Multi-Link communication with the target device based on the capability information of the self-device and the target device regarding Multi-Link communication. The so-called usage information regarding Multi-Link communication refers to the frequency channel or bandwidth used when the communication between the communication devices 102 and 103 is performed as Multi-Link communication. In addition, the details of the usage information of Multi-Link communication are described in FIG. 5 described later. Regarding the usage information, the determined usage information may be notified to the target device, or it may not be notified.

The connection processing unit 304 is a block for performing the processing required for the communication device 103, which is a STA, to participate in the network 101 constructed by the communication device 102. Specifically, the connection processing unit 304 causes the communication device 102 to send an Association Response frame as a response to the connection request, that is, the Association Request, received from the communication device 103. The communication device 102 has a connection processing unit 304 corresponding to each of the multiple links established by the device.

The MAC frame generation unit 305 is used to generate a block of a MAC frame containing information indicating capability information about Multi-Link communication generated by the capability information generation unit 301 or utilization information about Multi-Link communication determined by the utilization information determination unit 302. The MAC frame generated by the MAC frame generation unit 305 is included in at least one of the wireless frames of Beacon, Probe Response, and Association Response and is transmitted. In addition or in lieu thereof, the generated MAC frame is included in Reassociation Response and is transmitted. The capability information or utilization information contained in the MAC frame generated by the MAC frame generation unit 305 is represented by the Element shown in FIG. 5 described later.

The data transmission and reception section 306 is a block for transmitting and receiving data frames in the Multi-Link communication based on the utilization information about the Multi-Link communication determined by the utilization information determination section 302. In addition, the data transmission and reception section 306 can also transmit the wireless frame including the MAC frame generated by the MAC frame generation section 305 and receive the wireless frame from the target device.

In addition, although the communication device 103 has the same functional structure as the communication device 102, there are the following differences.

The communication device 103 does not have an application information determination unit 302, but instead has a request information determination unit 302. It is a block that determines the request information about Multi-Link communication with the target device based on the capability information about Multi-Link communication of the device and the target device. The so-called request information about Multi-Link communication refers to the frequency channel or bandwidth required to be used when the communication between the communication devices 102 and 103 is performed as Multi-Link communication. In addition, the details of the request information about Multi-Link communication are explained in Figure 5 described later. Regarding the request information, the determined request information can be notified to the target device, or it can not be notified.

The connection processing unit 304 is a block for performing the processing required for the communication device 103 to participate in the network 101 constructed by the AP, that is, the communication device 102. Specifically, the connection processing unit 304 enables the communication device 103 to send a connection request, that is, an Association Request, to the communication device 102, and enables it to receive an Association Response from the communication device 102 as a response.

Furthermore, the MAC frame generation unit 305 is used to generate a block of a MAC frame containing information indicating capability information on Multi-Link communication generated by the capability information generation unit 301 or request information on Multi-Link communication determined by the request information determination unit 302. The MAC frame generated by the MAC frame generation unit 305 is transmitted by being included in at least one of the wireless frames of Probe Request, Association Request, and Reassociation Request. The capability information or request information contained in the MAC frame generated by the MAC frame generation unit 305 is represented by an element shown in FIG. 5 described later.

FIG. 4 is a sequence diagram showing an example of processing performed when the communication device 102 and the communication device 103 perform Multi-Link communication.

The communication devices 102 and 103 have a connection processing unit 304 that internally corresponds to each of the plurality of links. AP1 of the communication device 102 is for the first link, and AP2 is for the second link. Furthermore, STA1 of the communication device 103 represents the first link, and STA2 represents the second link. STA1 and AP1 perform communication processing via the first frequency channel (e.g., 1ch of the 2.4GHz band). STA2 and AP2 perform communication processing via the second frequency channel (e.g., 36ch of the 5GHz band).

The processing of this sequence is started in response to the power-on of each of the communication devices 102 and 103. Alternatively, it may be started by at least one of the communication devices 102 and 103 in response to an instruction to start Multi-Link communication from a user or an application. Alternatively, it may be started by at least one of the communication devices 102 and 103 in response to the amount of data to be communicated with the target device reaching a predetermined threshold.

First, the communication device 102 transmits a Beacon containing the network information of the device in the first frequency channel, thereby notifying the surrounding STAs of the network information (S401). The so-called network information is specifically: the transmission interval of the communication device 102 for transmitting the beacon, or the SSID of the communication device 102. In addition, the communication device 102 can also include the Multi-Link Capability Element shown in FIG. 5 described later as network information in the Beacon, thereby notifying the communication device 102's capability information on Multi-Link communication.

Once the communication device 103 receives the Beacon of the communication device 102 transmitted in the first frequency channel, it transmits a Probe Request in the first frequency channel to query the network information of the communication device 102 (S402). The Probe Request includes the SSID of the communication device 103. In addition, the communication device 103 may also include the Multi-Link Capability Element shown in FIG. 5 described later in the Probe Request to notify the communication device 103 of the capability information related to the Multi-Link communication.

Once the communication device 102 receives the Probe Request, it sends the Probe Response to the communication device 103 in the first frequency channel as a response (S403). When the Beacon does not contain the Multi-Link Capability Element shown in FIG. 5, the communication device 102 includes the Element in the Probe Response and sends it. Alternatively, the communication device 102 may include only a part of the information included in the Multi-Link Capability Element shown in FIG. 5 described later in the Beacon, and include the remaining information or all the information in the Probe Response.

By performing the processing of S401 to S403, the communication devices 102 and 103 can exchange their respective capability information about Multi-Link communication.

Next, the communication device 103 sends a connection request, that is, an Association Request, to the communication device 102 in the first frequency channel. In this case, the communication device 103 may also include the Multi-Link Capability Element shown in FIG. 5 in the Association Request to notify the capability information of the communication device 103 regarding the Multi-Link communication. In addition, the communication device 103 may also determine the capability information to be sent in S404 based on the capability information of the communication device 102 regarding the Multi-Link communication obtained in at least one of S401 and S403. For example, even if the communication device 103 can combine the Links in the 2.4 GHz band and the 5 GHz band in Multi-Link communication, the communication device 102 can still only support multiple Links in the 2.4 GHz band. In this case, the communication device 103, as the capability information to be sent in this step, can also only send capability information about the establishment of multiple Links in the 2.4 GHz band. In addition, in this embodiment, although the communication device 103 sends the capability information about the Multi-Link communication of its own device in S402, it is not limited to this, and it is also possible not to send the capability information in S402, but only send it in this step. Alternatively, the communication device 103 may include the Multi-Link Capability Element shown in FIG. 5 in the Association Request, thereby sending request information required during the Multi-Link communication instead of the capability information. The request information required by the communication device 103 may be represented by the Multi-Link Capability Element of FIG. 5 or by another element. The details of the request information are described in FIG. 5 described later.

Once the communication device 102 receives the Association Request, it sends the Association Response to the communication device 103 in the first frequency channel as a response (S405). The Association Response sent here includes: a Multi-Link Capability Element that represents the usage information determined by the communication device 102 for the Multi-Link communication with the communication device 103. In addition, the usage information can also be represented by an element different from the Multi-Link Capability Element. In addition, if the Association Request containing the usage information required by the communication device 103 as an STA is sent in S404, the communication device 102 can also send an Association Response containing only the approval or disapproval of the request.

When the Multi-Link communication caused by the operation information included in the Association Response is executable by the communication device 103, the communication devices 102 and 103 establish a Link through the first frequency channel and start data communication (S406). In this case, when the operation information sent by the communication device 102 includes operation information of a Link through the second frequency channel, the communication devices 102 and 103 also establish a Link through the second frequency channel and start data communication (S407).

In addition, if the communication device 102 approves the request information sent by the communication device 103 in S404 in S405, the communication device 102 performs the processing of S406 in the same manner. Furthermore, if the request information sent by the communication device 103 in S404 also includes the request information about the link through the second frequency channel, the communication device 102 performs the processing of S407.

In this embodiment, although two links are established by sending and receiving signals in a frame in one frequency channel, the present invention is not limited thereto and three or more links may be established.

Furthermore, although the present embodiment discloses a case where Multi-Link communication is started from a state where Link has not been established between the communication devices 102 and 103, the present invention is not limited thereto. The communication devices 102 and 103 may also start Multi-Link communication by establishing a new Link in addition to the already established Link. In this case, when the communication device 103 as a STA has obtained the capability information about Multi-Link communication from the communication device 102 as an AP, the process may be started from S404. Alternatively, when the communication device 102 has obtained the capability information about Multi-Link communication from the communication device 103, the process may be started from S404 by sending a signal that causes the communication device 103 to send an Association Request. Alternatively, the communication devices 102 and 103 may also establish a new link in addition to the multiple links that have already been established. In this case, the sequence of FIG. 4 may also start from S404.

Furthermore, although the present embodiment discloses a case where a link through multiple frequency channels is established by sending and receiving signals in a frame in one frequency channel, the present invention is not limited thereto. When the communication devices 102 and 103 are performing Multi-Link communication, they can also disconnect the link through multiple frequency channels that have been established by sending and receiving signals in a frame in one frequency channel. For example, it is assumed that the communication devices 102 and 103 establish a first link through the first frequency channel and a second link through the second frequency channel, and are performing Multi-Link communication. In this case, it is assumed that either communication device 102 or 103 sends a Disassociation request for link disconnection to the target device via the first link. If the sent Disassociation contains information related to the second link, the communication devices 102 and 103 will disconnect not only the first link but also the second link. In this way, the communication devices 102 and 103 can also disconnect not only the link to which the Disassociation is received but also other links indicated by the information contained in the Disassociation by sending and receiving the Disassociation signal. In addition, the communication devices 102 and 103 can also disconnect more than three links at the same time. Furthermore, if the communication devices 102 and 103 include information related to another link different from the link to which the Disassociation is sent in the Disassociation, then only the other link may be cut off. In this case, the communication devices 102 and 103 may not cut off the link to which the Disassociation is sent.

As shown in FIG4 , the communication devices 102 and 103 can control the establishment or disconnection of links in other frequency channels by transmitting and receiving signals through a frame of a certain frequency channel (or link). Furthermore, the communication devices 102 and 103 can control the establishment or disconnection of links in a plurality of frequency channels by transmitting and receiving signals through a frame of a certain frequency channel (or link).

Fig. 5 is a diagram showing an example of the frame format of the Multi-Link Capability Element. In addition, in the present embodiment, although the element shown in Fig. 5 is named as Multi-Link Capability Element, it is not limited thereto and may be other names such as Multi-Link Element.

The communication devices 102 and 103 can notify the target device of capability information indicating the capability of the device in Multi-Link communication by using the Multi-Link Capability Element shown in FIG5. Furthermore, the communication device 102 can notify the target device of usage information during Multi-Link communication in addition to or instead of capability information by using the Multi-Link Capability Element shown in FIG5. Furthermore, the communication device 103 can notify the target device of requirement information during Multi-Link communication in addition to or instead of capability information by using the Multi-Link Capability Element shown in FIG5.

The Multi-Link Capability Element shown in FIG5 is composed of Element ID 501, Length 502, and ML (Multi-Link) Capabilities 503. Element ID 501 is an identifier required to identify the Information Element, and in this embodiment, it contains an identifier representing the Multi-Link Capability Element. Length 502 is a field representing the data length of the Element, and in this embodiment, it contains information representing the data length of ML Capabilities 503. ML Capabilities 503 is information inherent to the Multi-Link Capability Element, and contains information related to Multi-Link communication. Details of the information contained in ML Capabilities 503 will be described later.

In addition, the communication devices 102 and 103 generate the Multi-Link Capability Element shown in FIG. 5 in sequence starting from Element ID 501 and send them to other communication devices. In this case, the communication devices 102 and 103 generate and send all the fields in the signal frame. Specifically, the communication devices 102 and 103 generate and send all of Element ID 501, Length 502, and ML Capabilities 503 to other communication devices. Alternatively, the communication devices 102 and 103 may also send signals in parallel with the generation of the fields. Specifically, the communication devices 102 and 103, for example, send Length 502 in parallel with the sending of the generated Element ID 501.

The communication device 102, which is an AP, attaches a MAC frame containing the Multi-Link Capability Element to wireless frames such as Beacon and Probe Response and transmits them. Furthermore, the communication device 102 may attach a MAC frame containing this Element to wireless frames such as Association Response or Reassociation Response in addition to these wireless frames. The communication device 103, which is an STA, attaches a MAC frame containing the Multi-Link Capability Element to wireless frames such as Probe Request and Association Request and transmits them. Furthermore, the communication device 103 may attach a MAC frame containing this Element to Reassociation Request in addition to these wireless frames.

ML Capabilities 503 is composed of Common Info 511, Per Band Info 512, and Per Link Info 513. Common Info 511 is a field that indicates information common to all bands and links. Per Band Info 512 is a field that indicates information common to all links included in a specific band, and is information indicated for each band. Per Link Info 513 is a field that indicates information for each link.

Common Info 511 includes Primary Ch 521, Sync Mode Support 522, Async Mode Support 523, and Semi-Async Mode Support 528. Common Info 511 also includes Total Max Link Number 524, Band Combination Info 525, and Per Band Info Number 526. Common Info 511 also includes Per Link Info Number 527 and Device Type 529.

Primary CH521 is a field containing information indicating the frequency channel for sending and receiving management frames related to Multi-Link communication. The so-called Primary CH is the frequency channel used when sending and receiving management frames when the Link in Multi-Link communication is connected or disconnected. Specifically, it contains information indicating the frequency channel for sending and receiving Beacons containing Multi-Link Capability Element. The communication device 102, which is an AP, includes information indicating the frequency channel to be used when Beacons containing Multi-Link Capability Element send signals. The communication device 103, which is a STA, includes information indicating the frequency channel that receives the Beacon containing the Multi-Link Capability Element (that is, receives the Probe Request containing the Element). In this embodiment, information indicating the first frequency channel that transmits and receives the Beacon or Probe Request/Response in FIG. 4 is included. In addition, after the Multi-Link communication starts, if the frequency channel for transmitting and receiving the management frame of the communication devices 102 and 103 is changed, the Primary CH521 includes information corresponding to the changed frequency channel. Furthermore, in the Primary CH521, when any of capability information, usage information, or request information is expressed by the Element, information indicating a frequency channel on which transmission and reception of management frames are performed may be included.

Sync Mode Support 522 is a field containing capability information indicating whether the communication device 102 or 103 sending the Element supports the Sync Mode of Multi-Link communication. For example, if this field contains 0, it means that the communication device sending the Element does not support Sync Mode, and if it contains 1, it means that it supports Sync Mode.

In addition, when the Multi-Link Capability Element is used to indicate the use information, the Sync Mode Support 522 may be used to indicate whether the Sync Mode of the Multi-Link communication is to be executed. For example, when the communication device 102 sends an Association Response containing this Element, this field may indicate whether the Sync Mode is to be executed in the Link communication established by exchanging this association. In this case, for example, if this field contains 0, it indicates that the Multi-Link communication in Sync Mode is not to be executed, and if this field contains 1, it indicates that the Multi-Link communication in Sync Mode is to be executed.

Alternatively, when the Multi-Link Capability Element is used to indicate the request information, the Sync Mode Support 522 may be used to indicate whether the Sync Mode of the Multi-Link communication is required. For example, when the communication device 103 as an STA sends an Association Request containing this Element, this field may indicate whether the communication device 103 requires the Sync Mode of the Multi-Link communication. For example, if this field contains 0, it indicates that the Sync Mode of the Multi-Link communication is not required, and if this field contains 1, it indicates that the Sync Mode of the Multi-Link communication is required.

Async Mode Support 523 is a field containing capability information indicating whether the communication device 102 or 103 sending the Element supports the Async Mode of Multi-Link communication. For example, if this field contains 0, it means that the communication device sending the Element does not support the Async Mode, and if this field contains 1, it means that the Async Mode is supported.

In addition, when the Multi-Link Capability Element is used to indicate the use of the information, Async Mode Support 523 can be used to indicate whether the Async Mode of the Multi-Link communication is to be executed. For example, when the communication device 102 sends an Association Response containing this Element, this field can indicate whether the Async Mode is to be executed in the Link established by the exchange of this association. In this case, for example, if this field contains 0, it indicates that the Multi-Link communication in Async Mode is not to be executed, and if this field contains 1, it indicates that the Multi-Link communication in Async Mode is to be executed. In addition, when the use of the Element is used to indicate the use of the information, if the aforementioned Sync Mode Support 522 indicates that the Sync Mode is to be executed, this field will indicate that the Async Mode is not to be executed. Similarly, if Sync Mode Support 522 indicates that Sync Mode is not to be executed, Async Mode Support 523 indicates that Async Mode is to be executed.

Alternatively, when the request information is expressed by the Multi-Link Capability Element, whether the Async Mode of Multi-Link communication is required to be executed can also be indicated by Async Mode Support 523. For example, when the communication device 103 as an STA sends an Association Request containing this Element, this field can indicate whether the communication device 103 requires the execution of Async Mode in Multi-Link communication. For example, if this field contains 0, it means that the execution of Multi-Link communication in Async Mode is not required, and if this field contains 1, it means that the execution of Multi-Link communication in Async Mode is required.

Semi-Async Mode Support 528 is a field containing capability information indicating whether the communication device 102 or 103 sending the Element supports the Semi-Async Mode of Multi-Link communication. For example, if this field contains 0, it means that the sending device of the Element does not support Semi-Async Mode, and if it contains 1, it means that it supports Semi-Async Mode.

In addition, when the Multi-Link Capability Element is used to indicate the usage information, this field can also be used to indicate whether to execute the Semi-Async Mode of the Multi-Link communication. For example, when the communication device 102 sends an Association Response, this field can indicate whether to execute the Semi-Async Mode in the Link communication established by the exchange of this association. For example, if this field contains 0, it means that the Multi-Link communication in Semi-Async Mode is not executed. For another example, if this field contains 1, it means that the Multi-Link communication in Semi-Async Mode is executed.

Alternatively, when the request information is expressed by the Multi-Link Capability Element, this field can also be used to indicate whether the Semi-Async Mode of Multi-Link communication is required to be executed. For example, when the communication device 103 as an STA sends an Association Request, this field can indicate whether the communication device 103 requires the Semi-Async Mode of Multi-Link communication to be executed. For example, if this field contains 0, it means that the Semi-Async Mode of Multi-Link communication is not required to be executed. For another example, if this field contains 1, it means that the Semi-Async Mode of Multi-Link communication is required to be executed.

In addition, when the communication devices 102 and 103 perform Multi-Link communication, if they have been pre-set to use SyncMode, Async Mode, or Semi-Async Mode, these fields may be omitted. Specifically, Sync Mode Support 522, Async Mode Support 523, and Semi-Async Mode Support 528 may also be omitted.

Total Max Link Number 524 is a field containing capability information indicating the maximum number of links supported by the communication device 102 or 103 that sends the Element in Multi-Link communication. The so-called maximum number of links is the maximum number of links that can be established between the sending device of the Element and one target device. For example, when this field contains 3 as its value, it means that the sending device of the Element can establish up to three links for each target device. In this case, the sending device of the Element can maintain three links with one target device and maintain multiple links with other target devices at the same time. Alternatively, the so-called maximum number of links can also indicate the maximum number of links that the sending device of the Element can establish in Multi-Link communication regardless of the target device. In this case, for example, if this field contains 3 as its value, and the sending device of the Element has established 3 links with the target device, then the sending device is not related to the target device and cannot establish more links. The communication device 102 as an AP and the communication device 103 as an STA respectively include information indicating the maximum number of links that the device can simultaneously maintain in Multi-Link communication in this field.

In addition, when the utilization information is represented by the Multi-Link Capability Element, this field may also contain the number of links actually established in the Multi-Link communication. For example, when the communication device 102, which is an AP, sends an Association Response containing this Element, this field may represent the number of links established through the exchange of this association. Alternatively, it may also contain the maximum number of links that can be established in the Multi-Link communication with the communication device 103. In this case, the Total Max Link Number 524 may contain a value less than the smaller value of the maximum number of links that can be established by the self-device in the Multi-Link communication and the maximum number of links that can be established with the target device.

Alternatively, when request information is expressed by the Multi-Link Capability Element, this field may also include the number of Links required to be established in the Multi-Link communication. For example, when the communication device 103, which is a STA, sends an Association Request containing this Element, this field may indicate the number of Links that the communication device 103 requires to be established with the communication device 102. Alternatively, it may also include the maximum number of Links that can be established in the Multi-Link communication with the communication device 102. In addition, when the Multi-Link Capability Element is used to express the utilization information or request information, this field may also be omitted.

Band Combination Info525 is a field containing capability information indicating the frequency bands supported by the communication device 102 or 103 that sends the Element during Multi-Link communication. Table 1 shows an example of information represented by each bit of this field. In Table 1, each bit indicates whether a certain frequency band or a combination of frequency bands is supported. In this embodiment, when the bit contains 0, it indicates that Multi-Link communication of the content indicated by the bit is not supported, and when the bit contains 1, it indicates that Multi-Link communication of the content indicated by the bit is supported. For example, in the Band Combination Info525 sent by the communication device 102, when bit 0 contains 1, it indicates that the communication device 102 supports Multi-Link communication of different channels in the 2.4 GHz band. For example, when the value of Band Combination Info 525 is 0000111000, it indicates that the communication device 102 supports Multi-Link communication using multiple links of different frequency bands. In this case, it means that the communication device 102 does not support Multi-Link communication using multiple links of the same frequency band. Furthermore, by setting all bits of Band Combination Info 525 to 0, it can be indicated that the sending device of the Multi-Link Capability Element does not support Multi-Link communication. Alternatively, it can also indicate that the sending device of the Element is currently in a state where Multi-Link communication cannot be performed. In addition, the communication devices 102 and 103 may respectively support different frequency bands in communication with only one link and in Multi-Link communication. For example, when there is only one link communication, the communication devices 102 and 103 support all 2.4 GHz, 5 GHz and 6 GHz, but only support 5 GHz and 6 GHz in Multi-Link communication. In addition, the correspondence between each bit of Band Combination Info 525 and its content is not limited to that shown in Table 1. Moreover, the number of bits of Band Combination Info 525 can also be used to indicate more combinations of frequency bands or whether multiple links in other frequency bands can be established.

[Table 1] Bit content 0 2.4GHz band CH can communicate with each other Multi-Link 1 5GHz band CH can communicate with each other Multi-Link 2 6GHz band CH can communicate with each other Multi-Link 3 Multi-Link communication is possible between 2.4GHz and 5GHz channels 4 Multi-Link communication between 2.4GHz and 6GHz channels 5 Multi-Link communication is possible between 5GHz and 6GHz channels 6 Multi-Link communication is possible between 2.4GHz, 5GHz, and 6GHz channels 7 Reserved

In addition, when the Multi-Link Capability Element is used to indicate the usage information, the frequency band actually used in the Multi-Link communication can also be indicated in this field. For example, when the communication device 102 as an AP sends an Association Response containing this element, this field contains information indicating the frequency band of the link established by exchanging this association. For example, when the communication devices 102 and 103 establish a 2.4 GHz link and a 5 GHz link, the value of Band Combination Info 525 is 00001000.

Alternatively, when request information is expressed by the Multi-Link Capability Element, the frequency band required to be used in the Multi-Link communication may also be expressed in this field. For example, when the communication device 103, which is a STA, sends an Association Request containing this Element, this field may indicate the frequency band that the communication device 103 requests the communication device 102 to perform the Multi-Link communication. In addition, when the element is used to express the utilization information or the request information, this field may also contain capability information indicating the frequency band supported by the sending device of the element in the Multi-Link communication.

Per Band Info Number 526 is a field containing information indicating the number of Per Band Info contained in Per Band Info 512 described later. Per Band Info 512 contains a collection of Per Band Info for each band supported by the communication device 102 or 103 that sends the Multi-Link Capability Element in Multi-Link communication. Specifically, it contains information indicating the same number of bands as that indicated by Band Combination Info 525. In addition, in the Per Band Info 512 described later, the information of multiple bands is indicated by a common Per Band Info, but this is not limited to this. Furthermore, when Per Band Info 512 described later is omitted, this field is also omitted.

Per Link Info Number 527 is a field containing information indicating the number of Per Link Info included in Per Link Info 513 described later. Per Link Info 513 contains a set of Per Link Info for each link supported by the communication device 102 or 103 that sends the Multi-Link Capability Element in Multi-Link communication. When Per Link Info 513 described later is omitted, this field is also omitted.

Device Type 529 is a field containing capability information indicating what type of device the communication device 102 or 103 that sends the Element is in Multi-Link communication. Specifically, it contains information indicating which of the following four types of devices the sending device of the Element belongs to. The first type of device is a device that can simultaneously send data through a certain link and receive data through another link in Multi-Link communication. The second type of device is a device that can only send data through another link while sending data through a certain link. The third type of device is a device that can only receive data through another link while receiving data through a certain link. The fourth type of device is a device that can maintain multiple links at the same time, but cannot communicate data through another link while communicating data through a certain link.

In addition, when the Multi-Link Capability Element is used to indicate the usage information, Device Type 529 can also be used to indicate the type of device identity of the two devices in the Multi-Link communication. For example, when the communication device 102 sends an Association Response containing this element, this field can indicate the type of device identity of the device that is used in the Link communication established by exchanging this association. For example, when information indicating the second type is sent as the usage information, even if the communication device 102 is a device capable of operating as the first type, it still operates as the second type of device in the Link communication established by exchanging this association.

Alternatively, when request information is expressed by Multi-Link Capability Element, Device Type 529 can be used to indicate which type of device identity the communication device 103 is requested to act as in Multi-Link communication. For example, when the communication device 103, which is a STA, sends an Association Request containing this element, this field can indicate which type of device identity the communication device 103 wishes to act as in Multi-Link communication. For example, when this field contains information indicating Type 2, it indicates that the communication device 103 is requesting to act as Type 2 device in Multi-Link communication with the communication device 102.

Per Band Info 512 is a field composed of Band ID 531, Supported Bandwidth 532, Supported CH 533, and Async Mode CH Distance 534. In addition to these fields, Per Band Info 512 also contains Max Link Number 535 and Supported Nss 536. The set of Per Band Info 512 is included in the Multi-Link Capability Element for each frequency indicated by Band ID 531 described later.

Band ID531 is a field containing information for identifying a frequency band. Table 2 shows an example of the correspondence between the value contained in Band ID531 and the content indicated by the value. For example, when Band ID531 contains 0 as its value, Per Band Info512 containing this Band ID531 becomes information that is common to the Link of Multi-Link communication in the 2.4GHz band. In addition, the correspondence between the value contained in Band ID531 and the content indicated is not limited to this. In addition, more frequency bands can be indicated by increasing the number of bits of Band ID531.

【Table 2】 value content 0 2.4GHz band 1 5GHz band 2 6GHz band

Supported Bandwidth532 is a field containing capability information indicating the bandwidth supported by the communication device 102 or 103 that transmits the Element in the frequency band indicated by Band ID531. In addition, the bandwidth shown here indicates the bandwidth supported by each link when the sending device of the Element performs Multi-Link communication in the frequency band indicated by Band ID531. Table 3 shows an example of the correspondence between the value contained in Supported Bandwidth532 and the content indicated by the value. For example, when Supported Bandwidth532 contains 0 as its value, it means that the sending device of the Element supports a bandwidth of 20 MHz in the frequency band indicated by Band ID531. Furthermore, when the value of Supported Bandwidth 532 is 1 or greater, the transmitting device of the Element supports any bandwidth below the value when the Link of Multi-Link communication is established. For example, when the value of Supported Bandwidth 532 is 2, the transmitting device supports any of 20 MHz, 40 MHz, and 80 MHz as the Link bandwidth. Furthermore, the communication devices 102 and 103 may support different bandwidths when there is only one Link communication and when there is a Multi-Link communication. For example, the communication devices 102 and 103 support 80 MHz as their bandwidth in 5 GHz when there is only one Link communication, but may also support 20 MHz as their bandwidth in Multi-Link communication. In addition, the correspondence between the value contained in Supported Bandwidth 532 and the content indicated therein is not limited thereto. Moreover, more bandwidths can be indicated by increasing the number of bits in Supported Bandwidth 532.

【Table 3】 value content 0 20MHz bandwidth 1 40MHz bandwidth 2 80MHz bandwidth 3 160MHz bandwidth 4 240MHz bandwidth 5 320MHz bandwidth

In addition, when the Multi-Link Capability Element is used to indicate the usage information, the bandwidth actually used in the Multi-Link communication can also be indicated in this field. For example, when the communication device 102 as an AP sends an Association Response containing this Element, this field contains information indicating the bandwidth of the Link established by exchanging this association. For example, when the communication devices 102 and 103 establish a Link with a bandwidth of 40 MHz in 2.4 GHz, the value of Supported Bandwidth 532 is 1.

Alternatively, when request information is expressed by the Multi-Link Capability Element, the bandwidth required for use in Multi-Link communication may also be expressed in this field. When the communication device 103, which is a STA, sends an Association Request containing this Element, this field may express the bandwidth requested by the communication device 103 to the communication device 102. In addition, when the utilization information or request information is expressed by this Element, this field may also contain capability information indicating the bandwidth supported by the sending device of this Element in Multi-Link communication.

Supported CH533 is a field containing capability information indicating the channels supported by the communication device 102 or 103 that transmits the Element in the band indicated by Band ID531. In addition, the channels shown here are information indicating the channels that the communication device of the Element supports for Multi-Link communication in the band indicated by Band ID531. Table 4 shows an example of the correspondence between each bit of Supported CH533 and the channel indicated by the bit. For example, if a bit contains 0 as its value, it means that the communication device of the Element does not support the channel indicated by the bit, and if it contains 1 as its value, it means that the channel indicated by the bit is supported. For example, when the value of Supported CH533 includes 0000010010100, it means that the sending device of this field supports Multi-Link communication among 3ch, 5ch and 8ch. In addition, the communication devices 102 and 103 may support different channels when there is only one link communication and when there is multi-link communication. For example, the communication devices 102 and 103 support all channels 1 to 13ch when there is only one link communication, but only support some channels such as 1ch and 5ch in multi-link communication. In addition, the correspondence between each bit of Supported CH533 and its content is not limited to that shown in Table 4. Moreover, more channels can be indicated by increasing the number of bits of Supported CH533. For example, although only 2.4 GHz channels are shown as an example in Table 4, the number of bits can be increased and the 13th bit and later bits can be used to show the 5 GHz and 6 GHz channels. Alternatively, if Band ID 531 contains information showing 5 GHz, the 5 GHz channels can be shown in descending order starting from bit 0. Similarly, if Band ID 531 contains 6 GHz, the 6 GHz channels can be shown in descending order starting from bit 0.

【Table 4】 Bit content 0 1CH 1 2CH 2 3CH … … 12 13CH

In addition, when the Multi-Link Capability Element is used to indicate the usage information, this field may also indicate the channel actually used in the Multi-Link communication. For example, when the communication device 102 as an AP sends an Association Response containing this Element, this field contains information indicating the channel of the Link established by exchanging this association. For example, when the communication devices 102 and 103 establish a Link with a bandwidth of 1ch and 4ch in 2.4GHz, the value of Supported CH533 is 0000000001001.

Alternatively, when request information is expressed by the Multi-Link Capability Element, this field may also indicate the channel required to be used in Multi-Link communication. For example, when the communication device 103, which is a STA, sends an Association Request containing this Element, this field may indicate that the communication device 103 requests the communication device 102 to establish a link channel. In addition, when the element is used to indicate the usage information or request information, this field may also include capability information indicating the channels supported by the sending device of the element in Multi-Link communication.

Async Mode CH Distance534 is a field containing capability information of the channel spacing required by the transmitting device of the Element in the frequency band indicated by Band ID531 in Async Mode. In Async Mode, the communication of each Link is performed asynchronously, so if the channels used in each Link are too close, the communication may be interfered. How far apart the channels between Links should be so that the signals of each Link can be properly decoded varies depending on the communication device, so this field is used to notify the capability information. If Async Mode CH Distance534 contains 4 as its value, for example, it means that the transmitting device of the Element needs to maintain a channel spacing of at least 4 channels in Async Mode. In addition, if the aforementioned Async Mode Support 523 contains information indicating that the Async Mode is not supported, this field may contain 0 as its value, or this field may be omitted. In addition, in this embodiment, although the channel spacing required in the Async Mode is indicated for each band indicated by the Band ID 531, it is not limited to this, and it may also be designed to be common information for each band. Specifically, this field may also be included in the Common Info 511.

In addition, when the Multi-Link Capability Element is used to indicate the usage information, this field may also include information indicating the channel spacing actually used in the Async Mode of the Multi-Link communication. For example, when the communication device 102 as an AP sends an Association Response including this Element, this field includes information indicating the channel spacing of the multiple links established by exchanging this association.

Alternatively, when the request information is represented by the Multi-Link Capability Element, this field may also include information indicating the channel spacing required to be used in the Async Mode of the Multi-Link communication. It may also include information indicating the minimum channel spacing supported in the Async Mode of the Multi-Link communication with the target device. When the utilization information is represented by this element, this field includes: a value greater than the channel spacing of the larger channel spacing represented by the communication device 102 as capability information and the channel spacing represented by the communication device 103 as capability information. Furthermore, when Async Mode Support523 includes information indicating that Async Mode is not supported, or when Async ModeSupport523 is omitted, this field may include 0 as its value. Alternatively, this field may be omitted. Alternatively, when the communication device 103, which is a STA, sends an Association Request containing this Element, this field indicates the channel interval required by the communication device 103 in the Async Mode with the communication device 102. Furthermore, when the communication device 103 does not request the execution of the Async Mode, this field may contain 0 as its value, or it may be omitted. Furthermore, when the Multi-Link Capability Element is used to indicate the use information or request information, this field may be omitted.

Max Link Number 535 is a field containing capability information indicating the maximum number of Links supported by the transmitting device of the Element when Multi-Link communication is performed in the frequency band indicated by Band ID 531. Furthermore, when the aforementioned Band Combination Info 525 does not contain information indicating support for Multi-Link communication between Links in the same frequency band, this field may contain 0 as its value. Alternatively, this field may be omitted. Furthermore, in the present embodiment, although the maximum number of Links is indicated for each frequency band, this is not limited to this, and the maximum number of Links may be indicated as information common to all frequency bands. Specifically, this field may also be included in Common Info 511.

In addition, when the Multi-Link Capability Element is used to indicate the usage information, this field may indicate the total number of links actually used in the frequency band indicated by Band ID 531 in the Multi-Link communication. For example, when the communication device 102 as an AP sends an Association Response containing this element, this field contains information indicating the number of one or more links established by exchanging this association. For example, when the communication devices 102 and 103 establish two links in 2.4 GHz, this field contains 2 as its value.

Alternatively, when request information is expressed by the Multi-Link Capability Element, this field may also indicate the total number of Links required to be used in the frequency band indicated by Band ID 531 in Multi-Link communication. For example, when the communication device 103, which is a STA, sends an Association Request containing this Element, this field may indicate the number of Links that the communication device 103 requires to establish with the communication device 102. In addition, when the element is used to express utilization information or request information, this field may also include capability information indicating the maximum number of Links of the sending device of the element in Multi-Link communication.

Supported Nss536 is a field containing capability information indicating the maximum number of (spatial) streams supported by the transmitting device of the Element when Multi-Link communication is performed in the frequency band indicated by Band ID531. In addition, Nss is an abbreviation for Number Of Special Stream. The number of streams indicated in this field is the number of streams in MIMO communication. In addition, when MIMO communication is not supported during Multi-Link communication in the frequency band indicated by Band ID531, this field contains 0 or 1 as its value, or this field is omitted. Furthermore, in the present embodiment, although the maximum number of streams is indicated for each frequency band, it is not limited to this, and the maximum number of streams may also be indicated as information common to all frequency bands. Specifically, this field may also be included in Common Info 511.

Furthermore, when the Multi-Link Capability Element is used to indicate the utilization information, this field may indicate the number of streams actually used in the frequency band indicated by Band ID 531 in Multi-Link communication. For example, when the communication device 102 as an AP sends an Association Response containing this Element, this field includes information indicating the number of streams of the MIMO communication actually performed by the exchange of this association. For example, when the communication devices 102 and 103 perform MIMO communication with a stream number of 3 in the Link in which Multi-Link communication is performed in 2.4 GHz, this field includes 3 as its value. Furthermore, when MIMO communication is not performed, this field may include 0 or 1 as its value, or this field may be omitted.

Alternatively, when request information is expressed by the Multi-Link Capability Element, this field may also indicate the number of streams required to be used in the frequency band indicated by Band ID 531 in Multi-Link communication. When the communication device 103, which is an STA, sends an Association Request containing this Element, this field may indicate the number of streams required by the communication device 103 in MIMO communication during Multi-Link communication. Furthermore, when the communication device 103 does not request MIMO communication, this field may contain 0 or 1 as its value, or this field may be omitted. Furthermore, when the utilization information or request information is expressed by this Element, this field may also contain capability information indicating the maximum number of streams supported by the sending device of this Element in MIMO communication during Multi-Link communication.

Per Link Info 513 is composed of fields including Link ID 541, Band ID 542, Bandwidth 543, CH 544, and Nss 545. When the capability information is represented by the Multi-Link Capability Element, Per Link Info 513 indicates information about the channels that the sending device of the Element supports Multi-Link communication. In this case, the set of Per Link Info 513 contains as many copies as the number of channels (Links) that the sending device of the Element supports Multi-Link communication. Alternatively, when the capability information is represented by the Element and it is a Link for which Multi-Link communication has been established, Per Link Info 513 indicates information about the Link that has been established. In this case, the set of Per Link Info 513 may include as many copies as the number of established Links. Also, in this case, the Link for which the communication device 102 indicates information through Per Link Info 513 has been established with at least one of the communication device 103 and the other communication device. Also, in this case, the Link for which the communication device 103 indicates information through Per Link Info 513 has been established with at least one of the communication device 103 and the other communication device. Alternatively, when capability information is indicated through the Element, Per Link Info 513 may not be included. When utilization information is indicated through Multi-Link Capability Element, and the communication device 102 as an AP sends an Association Response containing the Element, this is not limited to this. In this case, Per Link Info 513 indicates information about the Link established by the exchange of this association. In this case, Per Link Info 513 includes as many copies as the number of Links established by the exchange of this association. Furthermore, when the communication device 103 indicates request information by sending an Association Request containing the Element, Per Link Info 513 indicates information about the Link that the communication device 103 requests to establish. In this case, Per Link Info 513 includes as many copies as the number of Links that the communication device 103 requests to establish.

Link ID541 is a field containing the identifier required to identify the link.

Band ID 542 is a field containing information indicating the frequency band to which the link indicated by Link ID 541 belongs. This field is indicated in the same manner as Band ID 531.

Bandwidth543 is a field containing information indicating the bandwidth in the link shown by Link ID541. This field is expressed in the same way as Supported Bandwidth532. In addition, when the capability information is expressed by Multi-Link Capability Element, this field indicates the bandwidth supported in the link shown by Link ID541. In addition, when the communication device 102 as an AP expresses the utilization information by sending an Association Response containing this element, this field indicates the bandwidth used in the link shown by Link ID541. Furthermore, when the communication device 103 as a STA indicates request information by sending an Association Request containing this Element, this field indicates the bandwidth requested by the communication device 103 in the Link indicated by Link ID 541.

CH544 is a field containing information indicating the frequency channels of the Link shown by Link ID541. This field may also directly contain the number of channels. Alternatively, the channels may be indicated as shown in Table 4. In addition, when the capability information is indicated by the Multi-Link Capability Element, this field indicates the channels supported in the Link shown by Link ID541. Furthermore, when the communication device 102 as an AP indicates the utilization information by sending an Association Response containing this Element, this field indicates the channels used in the Link shown by Link ID541. Furthermore, when the communication device 103 as a STA indicates request information by sending an Association Request including this Element, this field indicates the channel requested by the communication device 103 in the Link indicated by Link ID 541.

Furthermore, Nss545 is a field containing information indicating the number of streams of MIMO communication in the Link shown by Link ID541. Furthermore, when MIMO communication is not performed, this field may contain 0 or 1 as its value, or this field may be omitted. Furthermore, when capability information is expressed by Multi-Link Capability Element, this field indicates the maximum number of streams supported in the Link shown by Link ID541. Furthermore, when the communication device 102 as an AP expresses utilization information by sending an Association Response containing this Element, this field indicates the number of streams utilized in the Link shown by Link ID541. Furthermore, when the communication device 103 indicates request information by sending an Association Request containing this Element, this field indicates the number of streams requested by the communication device 103 in the Link indicated by Link ID 541.

By sending and receiving the MAC frame containing the Multi-Link Capability Element mentioned above, the communication devices 102 and 103 can exchange the capability information, usage information, and requirement information of the Multi-Link communication. In addition, in the present embodiment, the capability information, usage information, and requirement information of the Multi-Link communication are all represented by the Multi-Link Capability Element, but are not limited to this. Alternatively, the capability information and usage information or the capability information and requirement information may be represented by different Information Elements, respectively. In this case, for example, the capability information may also be represented by an Element containing Common Info 511 and Per Band Info 512. Furthermore, the usage information and requirement information may also be represented by an Element containing Common Info 511 and Per Link Info 513. Furthermore, when the capability information is expressed by the Multi-Link Capability Element, the fields related to some of the components may also express the usage information or the requirement information. Alternatively, when the usage information or the requirement information is expressed by the Multi-Link Capability Element, the fields related to some of the components may also express the capability information.

In addition, the Multi-Link Capability Element shown in Fig. 5 includes fields of Primary CH521, Supported CH533, and CH544 as information indicating frequency channels. However, the present invention is not limited thereto, and the Multi-Link Capability Element only needs to include at least one of Primary CH521, Supported CH533, and CH544 as information indicating frequency channels.

Furthermore, the name of each field, the number of fields, the order of fields, etc. are not limited to those shown in FIG. 5. Any field may be included before or after any field of the fields shown in FIG. 5. Furthermore, the fields included in Common Info 511 may also be included in Per Band Info 512 or Per Link Info 513. The fields included in Per Band Info 512 and Per Link Info 513 may also be included in the fields of the other party or in Common Info 511. Furthermore, any field shown in FIG. 5 may also be omitted.

FIG. 6 is a flowchart of a process in which a computer program stored in the memory unit 201 is read out and executed by the control unit 202 when the communication device 103 performs Multi-Link communication.

This flowchart is started when the power of the communication device 103 is turned on. Alternatively, the communication device 103 may start the Multi-Link communication in response to an instruction from a user or an application. Alternatively, the communication device 103 may start the Multi-Link communication in response to the amount of data to be sent to the communication device 102 reaching a predetermined threshold.

First, the communication device 103 obtains the Multi-Link communication capability information of the target device (S601). Specifically, the communication device 103 obtains the capability information of the communication device 102 by receiving a Beacon containing a Multi-Link Capability Element sent by the communication device 102. Alternatively, the communication device 103 may also perform the processing of this step by receiving a Probe Response containing a Multi-Link Capability Element sent by the communication device 102. In this case, the order of this step and S602 described later is reversed.

Next, the communication device 103 notifies the capability information of the Multi-Link communication of the own device (S602). Specifically, the communication device 103 notifies the capability information of the Multi-Link communication of the own device by sending a Probe Request containing a Multi-Link Capability Element. In the case where the capability information of the target device has been obtained before this step, the capability information to be notified by the own device can also be determined based on the capability information of the target device. Specifically, the communication device 103 determines the capability information to be notified in this step in a manner that does not exceed the capability of the communication device 102. For example, consider the case where the communication device 103 supports Multi-Link communications in 2.4 GHz, 5 GHz, and 6 GHz, while the communication device 102 only supports 2.4 GHz and 5 GHz. In this case, the communication device 103 notifies the communication device 102 of the fact that it supports 2.4 GHz and 5 GHz Multi-Link communication as capability information in this step. In addition, when the communication device 103 sends an Association Request containing request information indicating a request for Multi-Link communication to the communication device 102 in S603 described later, the processing of this step can also be omitted.

Next, the communication device 103 sends an Association Request containing request information for Multi-Link communication (S603). The request information sent in this step is information related to the Multi-Link communication that the communication device 103 requires to execute. In addition, in this step, the communication device 103 may also send an Association Request without request information.

The communication device 103 determines whether it has received the Association Response (S604) from the communication device 102 which is the AP. If the communication device 103 has not received the Association Response, it determines that it is No in this step and performs the processing of this step again. In addition, if a predetermined time has passed since the Association Request was sent in S603 and it is still not determined to be Yes in this step, the communication device 103 notifies the user of the error and ends the processing of this flow. On the other hand, if the communication device 103 has received the Association Response, it determines that it is Yes in this step and performs the processing of S605.

The communication device 103 starts the Multi-Link communication with the communication device 102 (S605). If the Association Response received in S604 contains the usage information of the Multi-Link communication, the Multi-Link communication starts based on the usage information. Alternatively, if request information is sent in S603 and an Association Response containing only the information indicating permission is received in S604, the Multi-Link communication starts based on the request information sent in S603. Once the communication device 103 performs the processing of S605, the processing of this flow ends.

FIG. 7 is a flowchart of a process in which a computer program stored in the memory unit 201 is read out and executed by the control unit 202 when the communication device 102 performs Multi-Link communication.

This flowchart is started when the power of the communication device 102 is turned on. Alternatively, the communication device 102 may start the Multi-Link communication in response to an instruction from a user or an application. Alternatively, the communication device 102 may start the Multi-Link communication in response to the amount of data to be sent to the communication device 103 reaching a predetermined threshold.

First, the communication device 102 notifies the capability information of the Multi-Link communication of the device (S701). Specifically, the communication device 102 notifies the capability information of the Multi-Link communication of the device by sending a Beacon containing a Multi-Link Capability Element. Alternatively, the communication device 102 performs the processing of this step by sending a Probe Response containing a Multi-Link Capability Element in response to receiving a Probe Response from the communication device 103. In this case, the order of this step and the later-described S702 is reversed.

Next, the communication device 102 obtains the Multi-Link communication capability information of the target device (S702). Specifically, the communication device 102 obtains the Multi-Link communication capability information of the target device by receiving a Probe Request containing a Multi-Link Capability Element. In addition, if the Probe Request containing a Multi-Link Capability Element is not received from the target device, the processing of this step can be omitted.

The communication device 102, upon receiving the Probe Request from the communication device 103, sends back a Probe Response as a response. In addition, in this case, if a Beacon containing a Multi-Link Capability Element has been sent, the Probe Response may not contain the Element.

The communication device 102 determines whether it has received the Association Request from the communication device 103 (S703). If the communication device 102 has not received the Association Request, it determines that it is No in this step and performs the processing of this step again. In addition, if a predetermined time has passed since the Probe Response was sent in S702 and it is still not determined to be Yes in this step, the communication device 102 notifies the user of an error and ends the processing of this flow. On the other hand, if the communication device 102 has received the Association Request, it determines that it is Yes in this step and performs the processing of S704.

Next, the communication device 102 sends an Association Response (S704) as a response to the Association Request. In the case where the communication device 102 does not receive the request information from the communication device 103 in S703, the communication device 102 sends an Association Response by including the usage information in the Multi-Link communication with the communication device 103. In this case, what usage information the communication device 102 should include in the Association Response is determined based on the Multi-Link communication capability information of the communication device 103. The usage information included in the Association Response and sent by the communication device 102 is information related to the Multi-Link communication actually performed between the communication devices 102 and 103. In addition, when the received Association Request in S703 contains request information from the communication device 103, the communication device 102 may still send an Association Response containing the usage information. In this case, the communication device 102 determines what usage information to include in the Association Response based on the request information from the communication device 103 in the received Association Request. Alternatively, when the communication device 102 receives the request information from the communication device 103 in S703, the communication device 102 may also send an Association Response containing only information indicating whether the Multi-Link communication is permitted.

The communication device 102 starts the Multi-Link communication with the communication device 103 (S705). When the Association Response sent in S704 contains the usage information of the Multi-Link communication, the Multi-Link communication starts based on the usage information. Alternatively, when the request information is received in S703 and the Association Response containing only the information indicating the permission is sent in S704, the Multi-Link communication starts based on the request information received in S703. Once the communication device 102 performs the processing of S705, the processing of this flow ends.

As described above, the communication devices 102 and 103 can perform Multi-Link communication taking into account each other's capabilities by including an element indicating the capability information of Multi-Link communication in the MAC frame.

In addition, at least a part or all of the flow charts of the communication devices 103 and 102 shown in FIG. 6 and FIG. 7 can also be implemented by hardware. In the case of implementation by hardware, for example, by using a predetermined compiler, a dedicated circuit is generated on the FPGA according to the computer program required to implement each step, and it can be used. The so-called FPGA is the abbreviation of Field Programmable Gate Array. In addition, a Gate Array circuit can be formed in the same way as FPGA and implemented in hardware. In addition, it can also be implemented by ASIC (Application Specific Integrated Circuit).

The present invention can also be implemented by providing a program that implements one or more functions of the above-mentioned embodiments to a system or device via a network or a storage medium, and having one or more processors in a computer of the system or device read and execute the program. Alternatively, the present invention can be implemented by a circuit (such as an ASIC) that implements one or more functions.

The present invention is not limited to the above-mentioned embodiments, and various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, in order to disclose the scope of the present invention, the following claims are attached.

This case claims priority based on Japanese patent application No. 2019-233222 filed on December 24, 2019, and all the contents of the application are hereby incorporated by reference.

101: Network 102: Communication device 103: Communication device 104: First link 105: Second link 201: Memory unit 202: Control unit 203: Function unit 204: Input unit 205: Output unit 206: Communication unit 207: Antenna 301: Capability information generation unit 302: Utilization information determination unit 304: Connection processing unit 305: Frame generation unit 306: Data transmission and reception unit 501~503,511~513,521~529,531~536,541~545: Fields

[Figure 1] Illustration of the configuration of the network to which the communication device 102 belongs. [Figure 2] Illustration of the hardware configuration of the communication device 102. [Figure 3] Illustration of the functional configuration of the communication device 102. [Figure 4] A sequence diagram of an example of the processing performed when the communication device 102 and the communication device 103 perform Multi-Link communication. [Figure 5] Illustration of an example of the message frame format of the Multi-Link Capability Element. [Figure 6] A flow chart of the processing performed by the communication device 103 when the Multi-Link communication is performed. [Figure 7] A flow chart of the processing performed by the communication device 102 when the Multi-Link communication is performed.

101: Internet

102: Communication device

103: Communication device

104: First Link

105: Second Link

Claims (19)

A communication device, characterized by comprising: a communication unit, which communicates with other communication devices by using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment unit, which establishes a plurality of links through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication unit contains: information indicating the minimum frequency interval of each of the aforementioned plurality of links required for the aforementioned communication device to perform communication in each of the aforementioned plurality of links in an asynchronous manner. The communication device as recited in claim 1, wherein the information indicating the aforementioned minimum frequency interval is information indicating the frequency interval that must be ensured at least between two of the aforementioned multiple links in order for the aforementioned communication device to perform communication in each of the aforementioned multiple links in an asynchronous manner. The communication device as recited in claim 2, wherein, when the communication in the aforementioned links is performed in an asynchronous manner, the aforementioned communication device performs communication control so that the communication using the aforementioned links can be performed in an asynchronous manner; when the aforementioned communication control is performed so that the communication in the aforementioned links can be performed in an asynchronous manner, the transmission of data in the first link among the aforementioned links and the reception of data in the second link among the aforementioned links can be performed at the same timing. A communication device, characterized by having: a communication unit, which communicates with other communication devices by using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment unit, which establishes a plurality of links through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication unit contains: a subfield that can represent information indicating the minimum frequency interval of each of the aforementioned plurality of links required for the aforementioned communication device to perform communication in each of the aforementioned plurality of links in an asynchronous manner. The communication device described in request item 1 or request item 4, wherein the MAC frame defined in the foregoing is at least one of a Probe Request and an Association Request. The communication device as described in claim 5, wherein the preamble communication unit includes information indicating the preamble minimum frequency interval between the preamble links of the preamble multiple links in a Multi-Link Element and transmits it. The communication device as described in claim 5, wherein the communication unit sends the MAC frame specified in the preceding paragraph before the establishment unit establishes the preceding plurality of links with the preceding other communication devices. A communication device, characterized by having: a communication unit, which communicates with other communication devices by using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment unit, which establishes a plurality of links including at least a first link and a second link through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication unit contains information indicating that the aforementioned communication device will not simultaneously transmit data in the aforementioned first link and receive data in the aforementioned second link in the aforementioned plurality of links. A communication device as described in claim 8, wherein the MAC frame defined in the foregoing is a management frame. A communication device as described in claim 9, wherein the aforementioned communication device sends a preceding management frame in a preceding first link among the preceding plurality of links, and does not send a preceding management frame in a link among the preceding plurality of links that is different from the preceding first link. A communication device, characterized by comprising: a communication unit, which communicates with other communication devices using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment unit, which establishes a plurality of links including at least a first link and a second link through different frequency channels with the aforementioned other communication devices; and a subfield that can indicate information indicating that the aforementioned communication device will not simultaneously transmit data in the aforementioned first link and receive data in the aforementioned second link in the aforementioned plurality of links in the aforementioned MAC frame that is communicated by the aforementioned communication unit. The communication device described in request item 8 or request item 11, wherein the MAC frame defined in the preceding note is one of Beacon, Probe Response and Association Response. The communication device as described in claim 12, wherein the aforementioned communication unit includes information indicating that the aforementioned communication device will not simultaneously transmit data in the aforementioned first link and receive data in the aforementioned second link in the aforementioned multiple links, in a Multi-Link Element and sends it. As described in claim 12, the communication device, before the establishment of the plurality of links between the establishment unit and the other communication devices, the communication unit sends the MAC frame specified in the preceding paragraph. A control method for a communication device, characterized by comprising: a communication step, which is to communicate with other communication devices by using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment step, which is to establish a plurality of links through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication step contains: information indicating the minimum frequency interval of each of the aforementioned plurality of links required for the aforementioned communication device to perform communication in each of the aforementioned plurality of links in an asynchronous manner. A control method for a communication device, characterized by comprising: a communication step, which is to communicate with other communication devices by using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment step, which is to establish a plurality of links through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication step contains: a subfield that can represent information indicating the minimum frequency interval of each of the aforementioned plurality of links required for the aforementioned communication device to perform communication in each of the aforementioned plurality of links in an asynchronous manner. A control method for a communication device, characterized by comprising: a communication step of communicating with other communication devices by using a MAC (Media Access Control) frame conforming to the IEEE802.11 series of specifications; and an establishment step of establishing a plurality of links including at least a first link and a second link through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication step contains information indicating that the aforementioned communication device will not simultaneously transmit data in the aforementioned first link and receive data in the aforementioned second link in the aforementioned plurality of links. A control method for a communication device, characterized by comprising: a communication step, which is to communicate with other communication devices by using a MAC (Media Access Control) frame that complies with the IEEE802.11 series of specifications; and an establishment step, which is to establish a plurality of links including at least a first link and a second link through different frequency channels with the aforementioned other communication devices; the predetermined MAC frame communicated by the aforementioned communication step contains: a subfield that can indicate information indicating that the aforementioned communication device will not simultaneously transmit data in the aforementioned first link and receive data in the aforementioned second link in the aforementioned plurality of links. A communication control program is used to enable a computer to execute a control method of a communication device as described in any one of claim items 15 to 18.

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